But the degree to which Brazilians have embraced biofuels today is truly staggering. Brazil is a world leader in biofuel technologies. More than 40% of Brazil's energy comes from biofuels and renewables. This year, over 90% of all new cars sold in Brazil will be flex-fuel vehicles, which can run on either gasoline or biofuels. Those cars can fill up at over 30,000 biofuel filling stations across the country.

In the search for new, sustainable economic models, the international community is coming to recognise the need for a radical rethink in relation to the generation of energy, and Brazil is responding by using clean, renewable, alternative energy sources to an ever-greater extent.

Indeed, in speeches now, Lula supposedly routinely calls on the rest of the world to join Brazil in "planting oil."

On the face of it, this is a bright green energy miracle, but things are not always what they seem.

There is, of course, first of all, the biofuel dilemma to be dealt with: that much energy is consumed growing the crops from which biofuels are made, and their production can cut into needed food production and carry other environmental costs.

One of the largest costs, in Brazil, is the destruction of the Amazon rainforest. Much of Brazil's biofuel production comes from soy beans, and soya production is one of the key drivers of rainforest destruction.

"Research shows that if Brazil was to implement an aggressive energy efficiency policy it could reduce the growth in power demand by as much as 40%, achieve energy savings of more than $37bn per year, and stabilise its power-sector related CO2 emissions by 2020. " ...

"But for biofuels to play a key role in a new carbon-free energy future, policy makers - both in the North and South - must ensure that biofuels are produced in an environmentally and socially friendly way. In Portuguese we have an expression which sums this up: Biocombustíveis sim, mas não de qualquer jeito! This means: yes to development but not to any development, yes to biofuels but not to any biofuels!"

David and Chad reported on still another possible answer in their piece last week on Terra Preta:

"Amazonian Dark Earth, or terra preta do indio, has mystified science for the last hundred years. Three times richer in nitrogen and phosphorous, and twenty times the carbon of normal soils, terra preta is the legacy of ancient Amazonians who predate Western civilization. Scientists who long debated the capacity of 'savages' to transform the virgin rainforest now agree that indigenous people transformed large regions of the Amazon into amazingly fertile black earth. The Amazonians' techniques remain an enigma but are believed to have used slash-and-smolder to lock half of the carbon in burnt vegetation into a stable form of biochar instead of releasing the bulk of it into the atmosphere like typical slash-and-burn practices.

"The difference between terra preta and ordinary soils is immense. A hectare of meter-deep terra preta can contain 250 tonnes of carbon, as opposed to 100 tonnes in unimproved soils from similar parent material, according to Bruno Glaser, of the University of Bayreuth, Germany. To understand what this means, the difference in the carbon between these soils matches all of the vegetation on top of them. Furthermore, there is no clear limit to just how much biochar can be added to the soil."

The widespread use of terra preta techniques is a long way off, if it's possible at all, but the combination of on-the-ground progress and looming innovation here is truly remarkable. Indeed, the potential here is that Brazil's carbohydrate economy offers one model of what a bright green energy system might look like.

Bravo Brazil! Today I was reading in the paper about a small rural town in Indiana that was renamed BioTown (or something like that). It's supposed to be this great venture/experiment in running a small community entirely on biofuels and ethanol. They made special efforts to get ethanol cars to the people and everything. Seemed like an uplifting story. But this ethanol-fed town is just missing one tiny thing....ethanol! D'oh! One day, our country will get something right. One day.

According to BPs recently released Statistical Review of World Energy 2006, Brazil consumed 664 million barrels of oil in 2005. In 2005, Brazil produced 4.8 billion gallons of ethanol, or 114 million barrels. However, a barrel of ethanol contains approximately 3.5 million BTUs, and a barrel of oil contains approximately 6 million BTUs. Therefore, 114 million barrels of ethanol only displaced 67 million barrels of oil, around 10% of Brazils oil consumption. In other words, Brazils energy independence miracle was 10% ethanol and 90% domestic crude oil production.

BTW, that's the breakdown by volume. By energy, diesel is ~140,000 BTU/gallon, gasoline ~126,000, natural gas probably measured as gasoline-equivalents, and ethanol is ~78,000 BTU/gallon. Sum it up, and Brazil's motor fuel (not even total liquids!) is only 10.5% by energy.